1. Field of the Invention
The present invention generally relates to communication systems. More particularly, the invention generally relates to controlling echo cancellation in a communication system.
2. Background Information
Some communication systems permit devices to communicate with each other via a “two-wire” line. Signals may be transmitted bi-directionally over the two-wire line from one device to the other, and vice versa. That is, bi-directional data may be present simultaneously on the same wire. One or both devices, however, may include a “hybrid” circuit to permit the conversion from a two-wire external line having both transmit and receive data to two separate communication paths within the communication device a transmit path including outgoing transmit data and a receive path including incoming receive data. The hybrid places the outgoing transmit data from the communication device's transmit path onto the common two-wire line and extracts the incoming receive data from the two-wire line and provides the extracted data to the communication device's receive path. As such, both transmit and receive data are processed by the hybrid.
An issue with such a communication system is “echo.” An echo generally is a reflection of the outgoing transmit signal which undesirably manifests itself through the hybrid as a signal that is superimposed on the incoming receive signal. It is thus desirable to reduce or eliminate the echo signal from the receive signal. Improvements in the area of echo cancellation is desirable.